Antiallergic and antiulcer 1-oxo-1H-thiazolo[3,2-a]pyrimidine-2-carboxamides and intermediates therefor

Abstract

Antiallergy and antiulcer agents having the formula (I), <IMAGE> (I) and their pharmaceutically acceptable salts, wherein R1 and R2 taken separately are each hydrogen or lower alkyl; and R1 and R2 taken together are alkylene of 3-9 carbon atoms or phenylalkylene of 9-11 carbon atoms, with the proviso that the ring so formed is between 5- and 8-membered; acids of the formula (II), <IMAGE> (II) wherein R1 and R2 are as defined above and R3 is hydrogen, which are useful as intermediates for compounds of the formula (I), but in many instances also possess the same useful biological activity as do formula I compounds; and intermediates of the formula II wherein R1 and R2 are defined as above, and R3 is alkyl of 1 to 4 carbon atoms, carbalkoxy of 2 to 5 carbon atoms, carbophenoxy or carbobenzoxy, are also described.

I claim: 
     
       1. A compound of the formula ##STR15## wherein R 3  is hydrogen; R 1  and R 2  taken together are alkylene of 3 to 9 carbon atoms or phenylalkylene of 9 to 11 carbon atoms with the proviso that the ring system so formed is 5- to 8-membered;   R 1  and R 2  taken separately are each hydrogen or lower alkyl of 1 to 5 carbon atoms, provided that when R 2  is hydrogen, R 1  is other than hydrogen or methyl and when R 1  is hydrogen, R 2  is other than methyl;   and cationic salts thereof.   
     
     
       2. A compound of claim 1, wherein R 1  and R 2  taken together are alkylene of 3 to 6 carbon atoms. 
     
     
       3. A compound of claim 2, wherein R 1  and R 2  taken together are butylene. 
     
     
       4. A method of inhibiting allergic reactions in a mammal which comprises administering to said mammal a compound of the formula ##STR16## or a pharmaceutically-acceptable salt thereof, wherein R 1  and R 2  when taken together are alkylene of 4 to 9 carbon atoms or phenylalkylene of 9 to 11 carbons, with the proviso that the ring system so formed is 5- to 8-membered, or, when taken separately, R 1  is alkyl or 2 to 5 carbon atoms, and R 2  is hydrogen or alkyl of 1 to 5 carbon atoms, in an amount sufficient to inhibit said allergenic reactions. 
     
     
       5. A method of claim 4 wherein R 1  and R 2  are taken together and are alkylene of 4 to 6 carbon atoms. 
     
     
       6. A method of inhibiting gastric ulcers in a mammal which comprises administering to said mammal a compound of the formula ##STR17## or a pharmaceutically acceptable salt thereof, wherein R 1  and R 2  when taken together are alkylene of 3 to 9 carbon atoms or phenylalkylene of 9 to 11 carbon atoms, with the proviso that the ring system so formed is 5- to 8-membered, and R 1  and R 2  when taken separately are each hydrogen or alkyl of 1 to 5 carbon atoms, with the proviso that when R 2  is hydrogen, R 1  is other than hydrogen or methyl, in an amount sufficient to inhibit said gastric ulcers. 
     
     
       7. A method of claim 6 wherein R 1  and R 2  are taken separately. 
     
     
       8. A method of claim 7 wherein R 1  is ethyl. 
     
     
       9. A method of claim 8 wherein R 2  is ethyl. 
     
     
       10. A method of claim 8 wherein R 2  is hydrogen.